You must be a video editor, right? I've seen the same clip on top of itself as many as 8 times in an OMF from a video editor. The answer to your question is that if you are manipulating the audio in any decent audio software, there is absolutely no need to stack clips on top of themselves.

Video-editors do it, because they don't have it under a fader and you can only boost a clip 6 to 12 dB. After that, stacking is the only way to get more gain from a super low level clip...

You must be an optimist at heart... I think video-editors do it because they just don't know any better. Maybe the raw footage was tracked and imported that way and they assume that stereo is better. If they knew what they were doing in regards to audio, wouldn't they know of other ways of raising the level without duping the clip?

Please. Don't. Double. Tracks. Makes for much extra confusion and work. Is that 2nd track a double or the audio from a different mic on the same talent. And etc. I've had video editors quintuple low-level tracks. People!

I actually found it helpful...but i pushed it to extremes.Allow me to explain:
I was recording a electric piano solo and found the sound to be quite thin and,well, GENERAL MIDI sounding..like the old 90's computer karaoke tracks.
So i went ahead and copied the track 16 times on my Yamaha AW16G DAW.
Yes it did make it louder but it also introduced a certain warmth and fullness that was not there before..so i tested it..I exported 1 track of it to a new song and later compared the 1 track version to the 16 track version and the 16 sounded fuller and more powerful.OFC the volumes were the same..i made sure they were.Were my ears playing tricks or did it really help?Who knows?

if you dropped 16 tracks into your daw exactly in phase.. you just increased gain. period. If you happened to end up with a bit of phase manipulation due to the DAW playing the 16 tracks at the same time due to problems in the playback because of your computer not handling 16 hits of the same file at the same time....and if there is some odd thing happening in any way... as soon as you record them down in the DAW its all back to just gain. Anything else is artifact you are hearing because of some issue with the playback... the bottom line is if you need to FIX the track do it with the original track and use some plugins... Not knowing what you are editing on, FCP, AVID, Premier, Protools, Logic and all the rest have simple plug-ins and many ways to increate the level of the file all the way to 0 db. if you need to kick the level of the single file that far, everything else needs to come down or you need to turn the volume up in your monitor system....

I've done it recording vocals many times. Many engineers double tracked vocals on albums for The Beatles, Stones, Elvis etc as it gives a cool reverb like effect of 2 different, quality vocal tracks together...I don't know for instrument tracks but for vocals its an old recording trick that is still cool, IMHO..

I've done it recording vocals many times. Many engineers double tracked vocals on albums for The Beatles, Stones, Elvis etc as it gives a cool reverb like effect of 2 different, quality vocal tracks together...I don't know for instrument tracks but for vocals its an old recording trick that is still cool, IMHO..

Again. Completely irrelevant to the original question.
Go back to the music forum please.

Yes it did make it louder but it also introduced a certain warmth and fullness that was not there before..so i tested it..I exported 1 track of it to a new song and later compared the 1 track version to the 16 track version and the 16 sounded fuller and more powerful.

When you compared, did you add enough gain to the one track to sound as loud as the 16 of them combined?
If yes, then the way you're applying gain is not proper, and in fact it may sound better by duping the tracks.
One of the trickiest things to program on a DAW or plugin is the gain. If it's not done properly, it is not going to sound right. There's a misconception that every gain is same but it is far from truth.
Only apply gain from trusted sources.

I've done it recording vocals many times. Many engineers double tracked vocals on albums for The Beatles, Stones, Elvis etc as it gives a cool reverb like effect of 2 different, quality vocal tracks together...I don't know for instrument tracks but for vocals its an old recording trick that is still cool, IMHO..

That's an EFFECT, right? Those were tracks with slight delays introduced (via tape head delay) on purpose. In this thread we are talking about simply duplicating a clip in the timeline of a DAW and putting it in exact sync on another track. If that track is panned the same as the original and has the same EQ etc etc then the result is that that clip plays louder. It is a cheeseball way of adding gain that causes confusion down the line.

You must be an optimist at heart... I think video-editors do it because they just don't know any better.

Hah... I was going to take offence to that (I've spent some time in both camps) but if I'm really honest, thinking back to some other video folk I've spoken to, I suspect you're probably right.

Sticking my neck out here - On SUPER SUPER low budget quickie jobs (which I usually try to avoid, but there have been occasions where bills have to be paid) where I've had to do both video & audio at once in Final Cut Pro, I have doubled tracks to increase gain on low-level source. FCP only allows a (IIRC) 12dB gain boost on clips, so when I'm under the hammer it can be faster to do a quick dupe rather than export, process offline, reimport and sync.

But I reiterate, that's only for quick + dirty all-in-one sessions. I would never EVER do that if I were planning to export the session.

I actually found it helpful...but i pushed it to extremes.Allow me to explain:
I was recording a electric piano solo and found the sound to be quite thin and,well, GENERAL MIDI sounding..like the old 90's computer karaoke tracks.
So i went ahead and copied the track 16 times on my Yamaha AW16G DAW.
Yes it did make it louder but it also introduced a certain warmth and fullness that was not there before..so i tested it..I exported 1 track of it to a new song and later compared the 1 track version to the 16 track version and the 16 sounded fuller and more powerful.OFC the volumes were the same..i made sure they were.Were my ears playing tricks or did it really help?Who knows?

I think we can caulk that one up to... Yes, your ears were playing a trick... and it's the same trick they always play. Ears are non-linear transducers and have different linear curves at different volume levels (see Fletcher-Munson Curve). As the volume goes up, your ears "hear" it differently than at a lower level. The "warmth" you experienced was probably this natural effect and you would have had the same experience by just adding gain to the single track version.